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--                  G E N E R I C _ E X P R E S S I O N S . E V A L           --

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--                                  S p e c                                   --

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generic
   with function "+" (X : Item) return Item is <>;
   with function "-" (X : Item) return Item is <>;
   with function "+" (X, Y : Item) return Item is <>;
   with function "-" (X, Y : Item) return Item is <>;
   with function "*" (X, Y : Item) return Item is <>;
   with function "/" (X, Y : Item) return Item is <>;
function Generic_Expressions.Eval (X : Expression) return Item;

